Optical waveguiding elements convey light from one point to another through an optically transparent, elongated structure by modal transmission, total internal reflection, and/or total reflectorization. An optical waveguide directs radiation in the visible, infrared, and/or ultra-violet portions of the radiation spectrum by total internal reflection.
This application further relates to tunable lasers. More specifically, and without limitation, to tunable semiconductor lasers using binary super gratings.